During normal usage last night (I simply deleted Facebook 1.6, as I periodically have, since I see saw between the ability to upload pics to my FB and ditching the memory leak), my phone powered off and rebooted. It makes it to the white screen, and seemingly just before the blue loader progress bar appears at the bottom, it reboots again.

I've tried leaving the battery out for a bit, leaving the memory card out, and I have it connected to my PC, but the best I get is "Removable Disk" in My Computer. I use the Loader app to try and load the OS -- I've tried selecting my PIN and Unknown in Step 2 of this process -- but I end up at the Device Application Selection window with a message of "The Blackberry Desktop Software does not have Blackberry Device Software for the device you have connected to this computer. Contact your wireless provider or System Administrator."